For many electromagnetic devices, deflection rings are utilized which consist of a ferrite pole core essentially in the shape of a truncated cone widened into a basin, onto which core a bundle of spirals is wound. To allow winding on winding machines, the firrite ring is initially divided into two parts, with each semicore thus having an open structure which can be wound on automatic winders; each semi-ring can thus be held on the winding machine by one of its lateral sections.
In windings presently done by machine, the turns are wound essentially along radial planes, i.e., passing through the axis of the truncated cone of the ring. Such an orientation of the turns is not advantageous electromagnetically, as it does not correspond to the best deflection output of the cathode-ray beam.
Of course it is possible to seek improvement in the performances of deflection rings by winding each turn on each semi-ring under the best orientations, for example by executing such a winding by hand. However, this would involve extremely long and costly operations hardly applicable industrially.
The object of the invention is to make is possible, without reducing the work speed of the winders of the machine, to obtain wound parts, in particular such as deflection rings for cathode-ray tubes, in which each wound turn has been wound according to the optimum orientation calculated for the function which the wound part is to fulfill.
Thus, for example, in the case of deflection windings for cathode-ray tubes having turns wound on each semi-ring in the form of a truncated cone widened into a basin, said turns can be inclined on radial planes symmetrically on either side of the median plane of each semi-ring, with two symmetrical bundles of spirals clearly separated from the median plane on the small section of the basin and in contrast essentially contiguous on the large section.
The process of the invention making it possible to achieve these objectives is characterized in particular by the fact that the core to be covered by the winding is held on a support, rotatable at all times around an axis X. Each winder is mounted so that its winding arm can turn around said core and around an axis Z guided obliquely in relation to an axis Y, itself guided obliquely in relation to said axis X, and at all times the rotation position .alpha. of said support around said axis X and the rotation position .beta. of the axis Z around said axis Y is selected and guided in order to obtain the various required successive planes for winding the turns around the core.
Preferably, in practice the axes X and Y are selected fixed in relation to one another and guided essentially orthogonally, as are the axes Z and Y.
According to another characteristic of the process of the invention, each core to be wound, such as an essentially truncated cone-shaped ferrite semi-ring, is attached to its support, essentially in its median plane and on its smaller section, and a perfectly symmetrical winding of spirals inclined in relation to this median plane is achieved by selecting winding programs at symmetrical angles .alpha. and .beta..
The invention likewise concerns a machine making it possible to implement the aforementioned process, this machine being characterized by the fact that it includes:
a bed-plate, PA1 at least one core support rotatable according to an angle .alpha. around an axis X fixed in relation to the bed-plate, PA1 at least one column supporting at least one winder mounted to turn on said column around an axis X fixed in relation to said column, PA1 said column being mounted to turn according to an angle .beta. in said bedplate around an axis Y fixed in relation to said bed-plate, PA1 said axes X, Y, and Z being guided obliquely in relation to one another. In practice and advantageously, the axes X and Y on the one hand and Y and Z on the other are arranged essentially orthogonally. PA1 initial control means making it possible to select at all times the angle position .alpha. and to cause to turn incrementally said core support around the axis X, PA1 secondary means of control making it possible to select at all times the angle position .beta. and to cause to turn incrementally said column around said axis Y, PA1 and means for pairing said initial and secondary means of control in order to obtain the various successive desired planes for winding the turns around the core.
According to another characteristic of the machine referred to in this invention, it includes in addition:
These pairing means consist advantageously of a microprocessor or computer storing the numbers of turns to be wound around the core for each value of the aforementioned determined angles .alpha. and .beta.. The winding program thus established, according to any known means existing in the field and within the reach of the specialist, controls the various motors of the machine, specifically the winder motors and the step-by-step motors for determining the rotation angle .alpha. of the support around the axis X and the step-by-step motors for determining the rotation angle .beta. of the column around the axis Y.
The invention will appear more clearly with the aid of the following description, with reference to the attached drawings in which: